diff --git a/drivers/scmi-msg/entry.c b/drivers/scmi-msg/entry.c
new file mode 100644
index 0000000..ea3efa2
--- /dev/null
+++ b/drivers/scmi-msg/entry.c
@@ -0,0 +1,63 @@
+// SPDX-License-Identifier: BSD-3-Clause
+/*
+ * Copyright (c) 2015-2020, Arm Limited and Contributors. All rights reserved.
+ * Copyright (c) 2019-2020, Linaro Limited
+ */
+
+#include <assert.h>
+
+#include <drivers/scmi-msg.h>
+#include <drivers/scmi.h>
+
+#include "common.h"
+
+void scmi_status_response(struct scmi_msg *msg, int32_t status)
+{
+	assert(msg->out && msg->out_size >= sizeof(int32_t));
+
+	memcpy(msg->out, &status, sizeof(int32_t));
+	msg->out_size_out = sizeof(int32_t);
+}
+
+void scmi_write_response(struct scmi_msg *msg, void *payload, size_t size)
+{
+	/*
+	 * Output payload shall be at least the size of the status
+	 * Output buffer shall be at least be the size of the status
+	 * Output paylaod shall fit in output buffer
+	 */
+	assert(payload && size >= sizeof(int32_t) && size <= msg->out_size &&
+	       msg->out && msg->out_size >= sizeof(int32_t));
+
+	memcpy(msg->out, payload, size);
+	msg->out_size_out = size;
+}
+
+void scmi_process_message(struct scmi_msg *msg)
+{
+	scmi_msg_handler_t handler = NULL;
+
+	switch (msg->protocol_id) {
+	case SCMI_PROTOCOL_ID_BASE:
+		handler = scmi_msg_get_base_handler(msg);
+		break;
+	case SCMI_PROTOCOL_ID_CLOCK:
+		handler = scmi_msg_get_clock_handler(msg);
+		break;
+	case SCMI_PROTOCOL_ID_RESET_DOMAIN:
+		handler = scmi_msg_get_rstd_handler(msg);
+		break;
+	default:
+		break;
+	}
+
+	if (handler) {
+		handler(msg);
+		return;
+	}
+
+	ERROR("Agent %u Protocol 0x%x Message 0x%x: not supported",
+	      msg->agent_id, msg->protocol_id, msg->message_id);
+
+	scmi_status_response(msg, SCMI_NOT_SUPPORTED);
+}